As the downward movement in the economy, many corporations still remains high expense on the debit. In order to lower the personnel expenses, technically, most corporations will directly lay off employees, or compress the working requisite, such as: unpaid leave, or deduction on the salary. After the downsize method has been conducted, there are some negative impacts on the employees (both to lay off and the remaining employee), this research will probe into the impact on the insecurity and commitment to the organization on remaining employees after the conduction of the downsizing method. According to the research result, it concluded the impacts from the downsizing method on increasing the insecurity at work, it will also affects remaining employees¡¦ trust to the company and further diminish the commitment to the organization. This research has examined the downsized corporations¡¦ remaining employees (to both general and managerial position employees) during July 2008 to February 2009 on the degree of insecurity and commitment to the organization. According to the examined result, this research has the following conclusion: 1.The downsizing method¡¦s actual impact on remaining employee¡¦s insecurity at work will be varied by the procedure, so the hypothesis is not approved. 2.The hypothesis on the remaining employees¡¦ insecurity at work has the negative impact on commitment to the organization, disapproved. 3.The hypothesis on downsizing by lay off and unpaid leave has the negative impact on commitment to the organization, approved; managerial and non-managerial position employee has the negative impact on the commitment to the organization, disapproved. 4.Insecurity from the downsizing method has a moderate effect on commitment to the organization; nevertheless, it can¡¦t approve the moderate impact on the insecurity at work from the downsizing method, so the result is insignificant.